Abstract

The existing security mechanisms in the Session Initiation Protocol (SIP)
are inadequate for cryptographically assuring the identity of the end
users that originate SIP requests, especially in an interdomain
context. This document defines a mechanism for securely identifying
originators of SIP messages. It does so by defining two new SIP
header fields, Identity, for conveying a signature used for
validating the identity, and Identity-Info, for conveying a reference
to the certificate of the signer. [STANDARDS-TRACK]